Matthias Kalle Dalheimer,
who besides being one of the initial KDE developers, author of a famous
c't article which helped galvanize KDE early in its life, author of an
important series of early KDE articles
(1,2,3)
as well as the author ofseveral
books on Qt development published byO'Reilly®, has recently
authored an article entitledDesign
Patterns in Qt. In it he explores how the
concepts from the "Gang of Four" bookDesign Patterns
are used in Qt programming, focusing specifically on Qt's signal-slot
architecture. Enjoy!

OK, I found the problem. It was RedHat's fault...
I updated my system to KDE 2.2.2 but for a strange reason RedHat didn't released all the KDE 2.2.2 rpm's at once.
kdebase-2.2.1-1 (and others) were still on my system

...is that Qt became a great symbiosis of design, for example by employing several design patterns, and functionality. Functionality in the sense that it still works on a wide range of platforms with equivalent power.

I've seen quite a number of projects which either became a pile of hacks (because it became apparent that certain compilers required certain workarounds. The business approach, so to say.) or a fairly well-designed but virtually unusuable collection of design patterns (because the authors refused to honour the importance of certain projects appropriately and instead insisted on clean code. You might call it the academic extreme).

As far as I've been able to figure out, there is of course a rather large number of hacks and workarounds in Qt as well, but those are very well hidden from the clients, so there's no need for guilty conscience or that "dirty" feeling. ;-)